This is the time of year for fifth disease

This is the time of year we begin to see fifth disease in schools. It is a benign viral disease of children usually seen in the late winter or early spring. Children with fifth disease appear with bright red cheeks and possibly a rash over their arms, legs and trunk. Fever is unusual and mild cold symptoms can be present.

Doctors today refer to it as parvovirus B19 infection or erythema infectiosum. Some people may call it slapped-cheek disease because of the face rash that develops resembling slap marks. Parvovirus infection is also commonly called “fifth disease” because it was fifth of a group of once-common childhood diseases with similar rashes. The other four are measles, rubella, scarlet fever and little-known Dukes’ disease.

Whatever the name, parvovirus infection is still a common but mild infection in children that generally requires little treatment. However, the infection in some pregnant women can affect the health of the baby. Transmission of the virus can cause fetal anemia which, if undetected, can have severe consequences.

The ill child typically has a “slapped-cheek” rash on the face and a lacy red rash on the trunk and limbs. Occasionally, the rash may itch. An ill child may have a low-grade fever, malaise, or a “cold” a few days before the rash breaks out. The child is usually not very ill, and the rash resolves in 7 to 10 days.

An adult who is not immune can be infected with parvovirus B19 and either have no symptoms or develop the typical rash of fifth disease, joint pain or swelling, or both. Usually, joints on both sides of the body are affected. The joints most frequently affected are the hands, wrists, and knees. The joint pain and swelling usually resolve in a week or two, but they may last several months. About 50% of adults, however, have been previously infected with parvovirus B19, have developed immunity to the virus, and cannot get fifth disease.

A person infected with parvovirus B19 is contagious during the early part of the illness, before the rash appears. By the time a child has the characteristic “slapped cheek” rash of fifth disease, for example, he or she is probably no longer contagious and may return to school or child care center. This contagious period is different than that for many other rash illnesses, such as measles, for which the child is contagious while he or she has the rash.

Fifth disease is usually a mild illness that resolves on its own among children and adults who are otherwise healthy. Joint pain and swelling in adults usually resolve without long-term disability.

There is no vaccine or medicine that prevents parvovirus B19 infection. Frequent handwashing is recommended as a practical and probably effective method to decrease the chance of becoming infected. Excluding persons with fifth disease from work, child care centers, or schools is not likely to prevent the spread of the virus, since people are contagious before they develop the rash.